Hi
Welcome to the HP Forums!
I appreciate you taking the time to share your concern and thank you for using this forum, it is a great place to find answers.
I reviewed your post and I understand that there is a shadow on the top right of your computer screen.
I’d love to help!
I recommend you to follow the steps in the below article under Image on screen has small dark or light dotsand check if it helps.
If the issue persists, I recommend you to boot to bios by tapping the F10 key on startup and check whether you see the shadow in bios as well. If the issue persists in bios, I recommend you to contact phone support as it might be a hardware issue.
Let me know how it works and you have a good day ahead.
To simply say thanks, please click the "Thumbs Up" button to give me a Kudos to appreciate my efforts to help. If this helps, please mark this as“Accepted Solution”as it will help several others with the same issue to get it resolved without hassles.
Take care!
Cheers!